Abstract: Through the cooperation with technology institutions,the development of low-carbon bainitic steel 590L grade is studied in the laboratory.The main work is composition design and CCT curve test of steel.According to the laboratory research results and combined with the 950 production line situation of Chuanwei,the industrial production plan of CW590L micro-alloy steel is optimized and practice is successfully put forward.The detection of microstructure and properties of the over 10 000 tons micro-alloy steel product shows that the average yield strength is 505 MPa,the average tensile strength is 630 MPa,the average elongation is 27% and the cold bending(d=1a) is completely qualified.The microstructure and properties fully satisfy the needs of the clients.